The separate physiological functions of cyclic nucleotide-dependent protein kinases will be studied. Hormonal activation of particulate-bound cAMP kinases will be investigate and translocation of subunits will be examined. The cyclic nucleotide kinase subunits will be purified and their functional domains will be identified, separated by treatment with proteases and then isolated. Their physical and kinetic characteristics and amino acid sequence will be thoroughly investigated. Non-protein kinase receptors for cAMP and cGMP will be identified, purified and characterized. The mechanism of hormonal activation of "low Km" phosphodiesterase will be examined and insulin effects on protein phosphorylation will be studied.